Building planks and boards

ABSTRACT

Improved building planks and boards consist of a metal tray (a) filled with a filling material (b). The sides of the tray may be grooved (c) enabling adjacent planks or boards to be assembled coplanar with pipes located in the oppositely facing grooves. The pipes serve to maintain the alignment of the planks or boards relative to one another and by circulating liquid through them enable an array of such planks and boards to be used in thermal transfer applications involving extracting heat from the environment or introducing heat to the array, for example for de-icing.

[0001] This invention relates to building planks and boards, particularly to such components adapted for use in thermal transfer applications within buildings.

[0002] There are many areas in the building and civil engineering industry which require the use of generally flat panel components. These are useful when constructing buildings, and in the finished buildings themselves. For example, it is customary to erect scaffolding on which the builders may work and, in order that they can do so comfortably, it is customary to arrange for successive decks defined by the scaffold structure itself, conventionally made of scaffold poles and joining fastenings, to be lined with planks or so-called builders' boards. These are traditionally made of wood, but, in more recent years, certain composite materials and structural plastics materials have also been used. It is also possible to produce builders' boards as metal fabrications, usually of aluminium or similar light alloy to enable them to be moved more easily than if they were made of steel.

[0003] Likewise in buildings themselves, modular components such as flooring sections and wall cladding, panels are known in a wide variety of materials including wood, reinforced concrete, plasterboard and the like.

[0004] We have now found that building planks and boards may be produced in a wide variety of shapes and sizes and for a variety of applications, especially thermal transfer applications, using simple fabrication techniques and a combination of an outer shell with an inner filling.

[0005] Thus, according to a first feature of the present invention, there is provided a building plank or board consisting of an external metal shell having located therein a structural material which is adhered to the interior of the shell.

[0006] Preferably the shell is in the form of a tray of appropriate shape and size and the filling substantially fills the tray as well as being adhered to the inner surface thereof.

[0007] Such adherence may be direct or indirect. In the case of certain filler materials, they are intrinsically adhesive to the metal tray. In the case of others, it is desirable either to treat the inside of the metal tray before the application of the filling material to ensure that adhesion occurs, or to interpose between the metal tray and the filling material a suitable layer of intermediate material to which both the tray and the filling adhere. A typical such intermediate material is an epoxy resin based composition. Additionally, or alternatively, the tray may have a plurality of tags or other formations around which the filling may locate. Punched tangs are a simple and convenient expedient. It is also possible with some filling materials to strengthen the joint between tray and filling by punching tangs from the tray material to engage with the filling after the filling has been put into the tray. Alternatively, a series of tags or studs may be welded to the interior of the tray before filling.

[0008] The tray is preferably made of steel or aluminium. Other metals may be used, but are generally less preferred on account of cost.

[0009] The filling may vary widely and may be, for example, asphalt, a resin-based composition, a cementitious competition, or a plaster-based composition. In any of these cases, the strength of the component may be materially increased by reinforcing the filler material with fibre materials. Fibre-reinforced compositions are well-known and a plurality of fibre types is available which can be easily and simply incorporated in such filler materials. The fibres of choice are glass fibres and polypropylene fibres, but other fibres such as mineral wool or other plastics fibres may also be used. For applications where substantial strength is desired of the load, more exotic fibres such as carbon fibres or Kevlar (Registered Trade Mark) fibres may be used.

[0010] A particular advantage of the modular building planks or boards according to the present invention is that they may easily be adapted for use in arrays with piping for heating or cooling applications. It is particularly preferred that the components of the present invention have edges with grooves in them enabling two such edges to be abutted with the grooves faring one another and receiving a pipe in the channel formed by the facing grooves.

[0011] This not only provides a way of securing heat transfer from or to a liquid in the pipe, but additionally the pipe itself acts to align two adjacent planks or boards together. By connecting pipes in appropriate circuits, the assembly of planks or boards may act thermally, for example as a thermal collector from which heat is extracted via liquid circulating in the pipes, or as a heat emitter. For example, if the boards are elongate thin slabs, laid side-by-side to form a floor, so-called “underfloor heating” can easily be achieved by circulating hot (relative to its environment) liquid through the system. Likewise runways or roadways may be made from an assembly of boards and may be de-iced by passing hot liquid through an array of pipes between them.

[0012] While the physical construction of the components in accordance with the invention may vary widely, a generally preferred construction is that of an elongate slab. This is illustrated by way of example in the accompanying drawings in which:

[0013]FIG. 1 is a perspective diagrammatic view of a plank in accordance with the present invention,

[0014]FIG. 2 is a cross-section thereof,

[0015]FIG. 3 is a cross-section through an alternative embodiment,

[0016]FIG. 4 is a perspective diagrammatic view of an alternative embodiment, and

[0017]FIG. 5 is a cross-section of a yet further embodiment.

[0018] It can be seen from FIGS. 1 and 2 of the drawings that the plank in accordance with the present invention there illustrated consists of an outer metal elongate trough a which is filled with a filling material b. Although not shown in the drawings, end pieces are customarily fitted to the outer casing a to enable the filling b to be placed in the casing in relatively fluent form and then converted therein to solid form adherent to outer casing b.

[0019] Also evident in FIGS. 1 and 2 is the semi-circular section groove running up each side of the component and denoted c in FIG. 2. As can be easily understood, if two elongate components are placed side-by-side and generally coplanar, the facing grooves c constitute a generally circular passage through which a tube may be run, both to hold the two adjacent components aligned with respect to one another and to allow thermal transfer to take place between a liquid in the pipe and the component itself.

[0020] As mentioned above, it is sometimes helpful to provide improved adhesion between the filling and the metal tray. Referring to FIG. 3, this shows a cross-section through a modular building component in accordance with the present invention where the trough a is first provided with two fillets of epoxy resin material denoted x in the drawing. The filling b is then placed in the tray, and the fillets x provide an enhanced bond between the trough and the filling.

[0021]FIG. 4 shows an alternative approach to increasing the resistance of the component to shear and tensile stresses. As seen in FIG. 4, the trough a has a series of punched tangs y located in its side walls. The tangs are of simple triangular shape formed by two cuts at an angle with the pointed section then being pushed towards the interior of the tray to form a triangular tag with the fold line constituting the third side of the triangle. A wide variety of other tang shapes may be envisaged, and the orientation of the tangs may vary from that shown in the drawing, either as a whole or differently oriented tangs may be produced in the same tray. It is generally found convenient to restrict the tang formation to the side walls of the tray so that, if the filling is introduced into the tray in fluid form, the base of the tray does not leak. When constructing such components, it is convenient to assemble a plurality of trays adjacent one another and with a tube located in the adjacent sections c, either itself of sufficient strength and rigidity to stop the outflow of tilling material into the generally circular section cavity between two adjacent trays, or a relatively floppy tube may be inserted between the trays and inflated to provide a barrier to the filling material emerging.

[0022] A further development is shown in FIG. 5. In the embodiment shown in this Figure, the tray is formed of extruded aluminium with a base and two extruded side sections z, each of which has an external outwardly-facing semi-circular groove in it. As shown in FIG. 5, the filling consists of two layers, for example of paper or fibre reinforced plasterboard which are separated by a bed of standard bonding plaster between them. The bonding plaster acts not only to adhere the two layers of plasterboard together, but additionally to secure them both within the tray.

[0023] All of the planks illustrated in the drawings may have appropriate finishes applied to them, either during manufacture or subsequently after assembly of the modular component, e.g. into a wall or flooring structure. For example, the components may be faced with appropriate decorative or wear-resistant surface materials.

[0024] In place of manufacture of individual boards or planks as suggested above, continuous manufacture may also be envisaged, including a first step of rolling to trough form a flat metal strip and fill up the trough with filler which, as the trough advances, sets to an extent enabling successive sections to be sawn off and stored until the filling has finally set or cured.

[0025] The detailed construction of planks and boards according to the present Invention may vary widely, and will depend in part on the envisaged use of the plank or board. Examples of three different types are as follows:

EXAMPLE 1 Steel Floor Trays

[0026] Galvanised sheet steel 0.65 mm thick is suitable for 225 mm wide planks with 19 mm hall rounds formed into the upstands. Pressed metal stop ends of the same material may be welded or adhesively attached to the trays. Alternatively 3 mm and upwards galvanised plate may be cut to the required profile and equally welded or adhered as stop ends. Planks pre-finished with tiles allow a rapid floor installation but, depending upon the strength characteristics required, the matrix and strengthening can be progressively increased to provide the desired characteristics. Simple synthetic anhydrite or proprietary self-levelling screeds may be poured into the trays with or without a bonding agent such as a styrene-butadiene resin.

[0027] Denser finishing plasters such as Armorcoat (Registered Trade Mark) may give better wearing surfaces and a more decorative appearance. Cement sand screeds are more dense and the cement slurry bonds well with the metal, but this again can be advantageously combined with a proprietary bonding agent based on styrene-butadiene resin or a styrene-acetylase polymer to provide better bonding. Cement sand is impervious, whereas the plaster finishes are susceptible to wafer and need wax finishing or other sealers to the surface. Polypropylene fibres are most readily combined with either cement or plaster (gypsum) matrices using existing mixing techniques, but, to achieve good fire resistance, glass fibres are preferred. Pilkington's Cemi-fil (Registered Trade Mark) with its concomitant specialist spray and mixing techniques can be advantageously used internally, whereas the lesser strength polypropylene fibres have better durability for external cementitious matrices. Plaster is not suitable externally and, for external applications, stainless steel trays containing a cement/fibre matrix may be preferred.

[0028] As strength requirements become more critical and increased spanning capacity is desired without increased structural depth, higher bonding strengths may be achieved with epoxy resin fillets, e.g. SIKADUR 32 (Registered Trade Mark), or more cheaply with tangs. For thermal transfer applications; the section depth is optimally restricted to about 50 mm. Encapsulated tubular elements are optimised around 65-75 mm for structural applications, whereas, for plumbing applications, 19 mm is the optimum. This allows sleeving of the more common copper and plastics pipe sizes of 15 and 16 mm. The plumbing pipes may be placed in direct thermal contact with the metal trays if the geometry is altered to specific plumbing pipe diameters and types such as cross-linked polyethylene.

EXAMPLE 2 Steel Wall Trays

[0029] Similar sizes apply to galvanised metal trays for walls where 19 mm steel conduit is a common component. Walls are not usually pre-finished, thus permitting custom decoration. Simple taped joints are common with plasterboard, as are special jointing compounds which are the painted over. Vinyl (usually white) is becoming more common as a pre-finish to plaster and plasterboard surfaces to facilitate cleaning. Whilst wallpaper can simulate marble patterns, the surface is more convincingly replicated with hard decorative ‘plaster’ surfaces including marble, brick dusts and a host of proprietary special finishes. Manufacturing techniques may involve continuous processes with wet filling and then de-watering, autoclaving, pressing or rolling the filling materials in the trays before cutting to length. Stop ends do not need to be used if the plank is made in a continuous process. Such continuous process manufacture can be used even when the filling is dry: for example, the filling may be of chipboard formed by introducing woodchips and resins into the tray, which can be formed continuously by standard metal roll-forming techniques. Precision extruded fired clay profiles (terracotta) can similarly be combined with resin ‘mortars’ and metal trays.

EXAMPLE 3 Asphalt Paving Trays

[0030] Aluminium roll-formed trays of 0.7 to 0.9 mm sheet may be filled with both traditional and polymer modified asphalt compositions using traditional techniques. Priming and bonding agents may be employed, but most installations will be fully supported, so improved structural performance is less important. Paving asphalt, sometimes used internally, may be more smoothly finished, include different colours, and/or be pattern imprinted. Fibres may be incorporated into the finishing toppings and be specially formulated for heavy duty paving applications. Extruded aluminium tray profiles (1.5 mm plus wall thickness) may employ the more heavyweight rolled asphalt techniques for thicker roadway surfaces to allow de-icing to be undertaken via the thermal conductivity of the trays, their infill material and encapsulated pipes located in an array between the trays. Solar collection is also possible via any of these asphalt surfaces. Night time re-radiation, so-called black body radiation, may be used at night to eject unwanted heat build-up via such asphalt paving trays. 

1. A building plank or board consisting of an external metal shell having located therein a structural material which is adhered to the interior of the shell.
 2. A building plank or board according to claim 1 wherein the shell is in the form of a tray and the filling substantially fills the tray and is adhered to the inner surface thereof.
 3. A building plank or board according to claim 2 wherein the filling is adhered to the interior of the tray, over at least a part of the interface between tray and filling, via a layer of epoxy-based composition.
 4. A building plank or board according to any one of claims 1 to 3 wherein the metal tray is provided with a plurality of shaped formations around which the filling is mechanically engaged.
 5. A building plank or board according to claim 4 wherein the formations are tangs punched from the material of the tray itself.
 6. A building plank or board according to any one of claims 1 to 5 wherein the filling is asphalt, a resin-based composition, a cementitious composition or a plaster-based composition.
 7. A building plank or board according to claim 6 wherein the composition is reinforced with a fibre material.
 8. A building plank or board according to claim 7 wherein the fibre material is glass fibre, polypropylene fibre or mineral wool.
 9. A building plank or board according to any one of claims 1 to 8 herein the edges of the plank or board are configured with grooves.
 10. A building structure consisting of an array of building planks or boards according to any one of the preceding claims with each abutting the next to provide an overall cladding to a floor, runway, roadway or wall. 